The future is links
The Google algorithm may penalise your website for too many irrelevant links to your website but other search engines do not. Also you should not ignore the amount of traffic that having links on high traffic sites bring you. So my advice would be that if a website has high traffic but is irrelevant to your subject it is still worthwhile getting a link for the traffic not for SEO purposes. Do this link “no follow” if it makes you more comfortable. But from my experience as long as you don’t get these links too fast you won’t suffer a penalty.